Efficient Quantum Network Communication using Optimized Entanglement-Swapping Trees

TL;DR

This paper introduces optimized entanglement-swapping trees and algorithms to significantly reduce latency in quantum network communication, enabling more efficient long-distance quantum entanglement distribution.

Contribution

It proposes a dynamic programming approach for optimal swapping-tree selection and an iterative algorithm for multiple pairs, improving efficiency over prior methods.

Findings

Outperforms previous approaches by an order of magnitude in simulations.

Enables viable long-distance entanglement generation.

Reduces latency in quantum network communication.

Abstract

Quantum network communication is challenging, as the No-cloning theorem in quantum regime makes many classical techniques inapplicable. For long-distance communication, the only viable communication approach is teleportation of quantum states, which requires a prior distribution of entangled pairs (EPs) of qubits. Establishment of EPs across remote nodes can incur significant latency due to the low probability of success of the underlying physical processes. The focus of our work is to develop efficient techniques that minimize EP generation latency. Prior works have focused on selecting entanglement paths; in contrast, we select entanglement swapping trees--a more accurate representation of the entanglement generation structure. We develop a dynamic programming algorithm to select an optimal swapping-tree for a single pair of nodes, under the given capacity and fidelity constraints. For the general setting, we develop an efficient iterative algorithm to compute a set of swapping trees. We present simulation results which show that our solutions outperform the prior approaches by an order of magnitude and are viable for long-distance entanglement generation.